And all of the "We want Phil" chants in the world aren't going to change that fact.
"Sometimes I feel I can still get out there and do it but the reality is I'm kidding myself," Jackson said during Wednesday's "Live Talks Los Angeles" event in Glendale, via Eric Pincus of the Los Angeles Times.
He still has the brains to guide an NBA team, and those 13 championship rings haven't gone anywhere. But the 67-year-old said the physical demands of life as a head coach are something his body just can no longer handle.
"When I was done I knew I was done—physically it was over," he said. "It's those long flights and three o'clock nights—getting up after five hours of sleep and going back to work, those are the things that wear you out."
That doesn't mean that a return to the league where he built a Hall of Fame career is out of the question.
"I have no intention of coaching," Jackson said. Translation? That front office gig he reportedly considered earlier this summer is still very much a possibility.
And if there is an executive position in his cards, he's already getting some valuable experience by helping his fiance, Los Angeles Lakers executive and part owner Jeanie Buss.
"I'm trying to counsel her on ways the team can improve," Jackson said. "They're a mess. We know that because of their financial disorder right now, that's the thing they have to get straight right away."
See Lakers fans, it's not that bad. Even if the Zen Master's coaching ship has sailed, he can still find a way to save this franchise.